Embodiments relate to an imaging system and, more particularly, to a system and method to obtain a high spatial resolution of information that would not be normally available when viewing a projected image, but is viewable when appropriate eyewear is used.
Steganography is an art and science of writing hidden messages in such a way that no one, apart from a sender and an intended recipient, suspects the existence of the message. Other than applying steganography techniques to assist in detecting counterfeited legal tender, such techniques are generally not used in association with typical activities involving consumers. For example, an approach using steganography to view closed caption information on a screen at a movie theater would be beneficial. Currently, there is no means to incorporate closed captioned information directly on a movie screen without all individuals viewing the movie seeing the closed captioned information. For example, glasses have been developed which use a receiver and transmitter to receive closed captioned information and then display it within the glasses for a wearer so that only the wearer sees the closed captioned information. These glasses with transmitters and receivers can be expensive to replace, repair and/or maintain. Other proposed approaches include using iPads®, tablets or cell phones to receive closed captioned information from the movie theater through Bluetooth® technology or a similar communication protocol, where the user could then watch the closed captioning on the device while watching the movie. Another tried option involved displaying the closed captioning on a back wall of the theater and watching the movie through a “window” at the user's seat. The window would reflect the closed captioning to the user. However, these approaches have tended not to be acceptable by the viewing public or by theater owners.
Because of the cost associated with having such glasses requiring transmitters and receivers, another approach is to encode the closed caption directly onto the movie, but making the closed caption only available to certain users, such as those wearing a particular type of glasses. One approach involved a use of an ordinary liquid crystal display (“LCD”) between the projector and viewing screen. However, the resultant images were found to be blurry due primarily to diffraction, which is a result of shapes of pixels of the LCD, which are a smallest addressable element of the LCD, having sharp edges. The pixels are usually provided in a two-dimensional grid, and are often represented using dots or squares. Though pre-compensation may be used to sharpen an image viewed on a movie screen, an amount the images may be sharpened is limited by a dynamic range of the encoding system, which relates back to the pixels.
If a viewer of images on the movie screen desired to view information that would not be normally available for viewing, such as, but not limited to, closed captioned information or subtitles, such viewers would not be able to see the closed caption or subtitles unless the entity operating the projection system activated that feature. However, in activating the closed caption or subtitles feature, all viewers of the images would see the closed caption or subtitles as well. Thus, manufacturers, users and consumers would benefit from being able to be provided information where the information is not readily visible to others, but through a form of steganography such information may be viewable by specific viewers where the information has clear resolution.